Intake Gasket Woes

[bpd106]

Well I put my new JBM carb boots on today and used a sheet of Mr Gasket 1/16" material and made my own gaskets. Low and behold, they're not sealing. I used the stiff paper type gasket sheet, almost cardboard like. Are you guys that are making your own gaskets using the cork/rubber type or the kind I just described? The only thing I did find is that the longer it ran the worse the leak got. I pulled the carbs off and the boot bolts were not as tight as I had snugged them down initially. I'm assuming the gaskets compressed. I tightened them back up and was gonna try it again tomorrow evening to see if they compressed anymore. If all else fails, I'll just have to order a set of gaskets. Oh, and I put one of the manifolds on without the gasket and it definitely needs one. I can seen light between it and the head without the gasket.
Any suggestions? Comments? etc? BTW, JBM is an awesome company. Sorry not sure how the "thumbs up" got on my title???

Thanks,
bpd106

 

[weekendrider]

You might try soaking/coating the gasket in oil so they will swell alittle?

 

[5twins]

..... and use washers under the mounting bolt heads so they don't sink into the manifold. Originals had that metal shroud over them to stop this.

 

[blackbetty]

Edelbrock gasgacinch helps with this.

You apply it to both surfaces of the gasket, and then on the block surface. Seals the gaskets and makes em stick in place when you install the part.

 

[littlebill31]

Permatex baby!

 

[Sundie]

yamabond. or the 1194 stuff Mike's sells. Non-setting sealant, apply a skim coat to both the head and the JBM flange, wait 5 - 10 mins for setup, washer on the bolt, blue loctite on the the threads. Tighten to about 5 - 7 lbs (basically, landed, then about 1/2 turn more or less).

Guaranteed to work.

 

[gggGary]

put a straight edge on the engine flanges to be sure they are flat some PO may have warped them somehow..

 

[bpd106]

It looks like the left carb boot has a slight imperfection on the back flat mounting surface where it meets the engine flange which is causing the leak. I did the 'ol starter fluid test and the revs go up when I spray it near where I thought the little bit if mishaping is is. I'll prolly order up a set of the intake gaskets for this thing, and use the permatex that I have. I just don't think that the 1/16" gasket material I have is enough to seal it up. The imperfection is right where the vacuum tube is on the left boot. The right one seems to be sealing up just fine. I looked all over the city for 1/8" gasket material and the only kind I can find is the cork rubber type. These are all great suggestions but if you guys got anymore, I'm definitely open to them.

Thanks,
bpd106

 

[azman857]

Talk to JBM and see about a replacement. You paid good money for a good product then you should get a good product. If it has a manufacture defect they should replace it. Now if your mounting surface is wonky somehow, you gotta get it fixed somehow.

 

[bpd106]

I've got a set of gaskets on the way. If I can't get them to seal after trying it with the gaskets that are made for it, then I'll give JBM a call. It looks like when they put the vacuum tube in, it caused the mounting surface of the boot to indent slightly. I laid a straight edge across it and the right one, and the left is definitely just a little out of shape. The flange on the blocks look to be nice and even.
I didn't wanna call JBM and whine just yet, but I may have to lol!!
Thanks,
bpd106

 

[Classic]

The guy that runs JBM is a good guy. I'm pretty sure he'd work with you to get this sorted. I have also heard from quite a few people that a proper JBM can be used with no gasket and that is how it is designed to be run.

 

[Punkskalar]

No gaskets here JBM intakes work pretty well without em'

 

[xjwmx]

will the original metal shroud fit on the jbm'ers ?

 

[Punkskalar]

will the original metal shroud fit on the jbm'ers ?

Nope.... The JBM's are built much thicker

 

[littlebill31]

When I talked to him he said I could go without a gasket, but it depended on the intake surface though. He also noted that the vacuum barb can weaken the interior metal in the boot and, as stated on the site, to use a carb vacuum adapter instead of the barb. I see no problem with the barb though. Feels damn strong to me.